Internal combustion engine



Sep 1940- A.'GARVE' r A; 2,216,074

INTERNAL COBUSTION ENGINE Filed Oct. 24, 1938 Rotated. B9 The" CranK Jhajt Patented Sept. 24,1940 l 2,216,074

INTERNAL COMBUSTION ENGINE Alexander Garve and Oskar Kurtz, Augsburg,

Germany,- assignors to Maschinenfabrik Augsburg-Numberg A. G., Augsburg, Germany, a corporation of Germany Application October 24, 1938, SerialNo. 236,647 In Germany November 9, 1937 5 Claims. (01. 123-65) For loading internal combustion engines of draws the air through a branch piping 9 from ground-bound vehicles as well as of airplanes. the scavenging air piping'i. The more highly Roots blowers and radial blowers are hitherto compressed air is directed to the cylinder I almost exclusively used for obtaining or genthrough the pressure piping I and the rotary crating the loading or charging air. But since slide valve I. In order to effect this, the shaped- 5 in two-cycle internal combustion engines of high out portion ll of the rotatable member l2 of the performance; for instance,'airplane motors of slide valve must first be got into position to highest performance very large quantities of air connect the pipings ill and I3.

are needed for scavenging, it was found that Agreeable to the purpose the compressor 8-2- radial blowers were hardly suited for this kind gregate is driven jointly by one and the save 10 10 of engines. It has for this reason already been waste gas turbine; if however the loading is to tried to make use of axial blowers for loaded be done only at intervals each separate blower two-Cycle internal combustion ehgil'les- There may be driven by its own waste gas turbine or by arises however the disadvantage that for gen any outside source of power.

crating the more highly tensioned or compressed We claim: 15 air, a relatively large number of blower stages 1. In combination, a two-cycle internal comare necessary since in axial blowers pressure rises bustion engine cylinder, a radial blower for genfrom stage to stage only by low steps. The loadcrating comparativly high pressure charging air i s blowers would c n qu ntly be ulky and for said cylinder, and a second blower for genheavy. erating comparatively low pressure scavenging 20 A c n to he inv nti n h se is v n air for said cylinder, and with a much greater are avoided by generating the scavenging and the volumetric capacity output than said radial loading y a ggregate of two blowers of blower, said second blower having inlet and disdifierent d, t at is an axial b r f 8 charge passages and a series of rotatable blades crating large q t ies l w-t ns providing an axial flow of air from the inlet pas- 25 scavenging air, and a radial blower for generating sage t t discharge passage and means supplya s r q y of hlgh-tehsioned loading a ing air compressed by said blowers to the cyl- The use of two diflerent kinds of blowers in a i d joint air compressor is particularly advantageous 2, In combination, a two-cycle internal combecause each blower may be used o y for that bustion engine cylinder, a radial blower for gen- 0 Portion of the compression for which it S 1 erating comparatively high pressure charging air cially suitable. For instance in a compressor agfor said cylinder, and a second blower for gent according the invention, an axial blOW- erating comparatively low pressure scavenging r having at most three Stages is sufficient The air for said cylinder, and with a much greater d a blower, if not Sucking t directly from volumetric capacity output than said radial blow- 35 e atmosphere, may draw it from the compreser, said second blower having inlet and discharge sion chamber of t e a al b ow S there i passages and a series of rotatable blades providalways n ly large q y f l ing an axial flow of air from the inlet passage to able, this may be done without materially intert discharge passage, means supplying air comferins wi h h generation of scavenging irpressed by said blowers to the cylinder, and an 40 In the drawing a preferred form of the blower xhaust gas turbine operated by exhaust gases ag e according o the invention s ShOWnfrom said cylinder for driving said blowers.

The ven i r necessary for h scaveng- 3. In combination, a two-cycle internal coming of the cylinder l of a two-cycle internal combustion engine cylinder having an air supply bustion-engine is generated by an axial blower opening, a radial blower for generating 'compara- 45 3 with, in the present case, a single stage. This tively high pressure charging air for said cylinblower is secured on a shaft 2 which is driven by der, and a second blower for generating com;-

a waste gas turbine 4 on the same shaft. The paratively low pressure scavenging air for said waste gases flow directly from the cylinder I cylinder, and with a much greater volumetric through the piping 5 to the turbine 4. The lowcapacity output than said radial blower, said sec- 50 tensioned scaven ing 7 air generated by the axial ond blower having inlet and discharge passages blower 3 is sentto the cylinder i through the and a series of rotatable blades providing an piping 6 and the rotary slide valve 1. The raaxial flow of air from the inlet passage to the dial blower 8 for generating th charging or sudischarge passage, an air supply pipe communiperchargi rig air is also secured (it. the shaft 2 and eating with the air supply opening of the cylinder, and a valve operable to connect said pipe either to the output side of the radial blower or to the utput side of the second blower.

4. In combination, a two-cycle internal combustion engine cylinder having an air supply opening, a radial blower for generating comparatively high pressure charging air for said cylinder, and a second 'blower for generating comparatively low pressure scavenging air for said cylinder, and with a much greater volumetric capacity output than said radial blower, said second blower having inlet and discharge passages and a series of rotatable blades providing an axial flow of air from the inlet passage to the discharge passage, a pipe connecting the discharge passage of the second blower to the inlet passage of the radial blower, an air supply pipe communieating with the air supply opening of the cylinder, a valve operable to connect said last-mentioned pipe either to the outut side of the radial blower or to the output side of the second blower,

\ viding an axial flow of air from the inlet passage to the discharge passage, a pipe connecting the discharge passage of the second blower to the inlet passage of the radial blower, means supplying air compressed by said blowers to the cylinder, and an exhaust gas turbine operated by exhaust gases from said cylinder for driving said blowers.

ALEXANDER GARV'E. 2o

OSKAR KURTZ. 

